Wide Binaries
Gaia DR3Wide binary star systems — two stars orbiting each other at separations of thousands of AU — provide one of the cleanest tests of gravity in the low-acceleration regime. Synchronism makes a specific, testable prediction about these systems that differs from both Newtonian gravity and standard MOND.
Why Wide Binaries?
At separations greater than ~104 AU (roughly 0.05 parsecs), the gravitational acceleration between two stars drops below a₀ ≈ 1.2 × 10−10m/s². In Newtonian gravity, nothing special happens. In MOND, orbital velocities should be higher than Newtonian predictions. The anomaly — if it exists — should be visible in the orbital dynamics.
The beauty of wide binaries is simplicity: two gravitating masses, no dark matter halo ambiguity, no complex baryonic physics. It is the closest thing to a clean two-body test of modified gravity.
Synchronism's Prediction
Standard MOND predicts the same anomaly regardless of where the binary system is located. Synchronism predicts something different:
Density-Dependent Anomaly
The wide binary anomaly should depend on local environment density. Binaries in dense stellar neighborhoods (near the Galactic plane, in open clusters) should show a weaker anomaly than binaries in low-density environments (high Galactic latitude, far from molecular clouds).
This follows directly from the coherence function: higher ambient density shifts ρcrit, altering the acceleration threshold at which modified dynamics appear. In dense environments, the external coherence field “masks” the low-acceleration effects.
The Data
The European Space Agency's Gaia mission (Data Release 3) provides the necessary measurements: positions, proper motions, parallaxes, and radial velocities for over a billion stars. From this, wide binary candidates can be identified and their orbital dynamics characterized. Gaia Archive (ESA) →
Current Observational Status
Several groups have analyzed Gaia wide binaries with conflicting results. Chae (2023) reported a clear anomaly consistent with MOND. Banik et al. (2024) found no significant anomaly. The disagreement centers on sample selection, contamination from unresolved triples, and statistical methodology.
Synchronism's environment-dependent prediction offers a potential resolution: both groups may be correct for their respective samples if the anomaly depends on local density. This can be tested by binning existing catalogs by Galactic latitude, local stellar density, and distance from the Galactic plane.
Why This Test Is Decisive
If confirmed
A density-dependent wide binary anomaly would strongly support the coherence framework. Neither standard MOND nor CDM predicts this pattern. It would be a genuine new prediction confirmed by data.
If refuted
If the anomaly shows no environment dependence (or doesn't exist at all), it falsifies the coherence-based mechanism for modified gravity. The galactic-scale results would need a different explanation.
This is one of the cheapest decisive experiments in fundamental physics: the data already exists, the analysis requires computational resources but no new observations, and the prediction is specific enough to be clearly confirmed or refuted.